10 hours ago
- Northwestern University scientists demonstrated that entangled photons can coexist with high-capacity internet traffic in the same fiber-optic cable over a 24.4 km link between Evanston and Chicago.
- The experiment preserved entanglement fidelity above 94% despite the cable carrying two 800 Gbps data channels and additional optical power equivalent to a fully loaded commercial link.
- To protect fragile quantum signals, the team shifted photons to the O-band (a quieter spectral region) while classical data remained in the C-band, and used a White Rabbit optical timing system for picosecond-level synchronization.
- This study, published in Optica Quantum, marks the first demonstration of entanglement distribution over a fiber simultaneously carrying modern commercial telecommunications traffic.
- The researchers plan to next perform quantum teleportation between remote nodes across a real-world metropolitan fiber network carrying commercial traffic.